Resilient contact pins of electrical connectors often include a plunger guided linearly in a slot with a separate compression spring for producing spring-biased travel of the plunger in the slot. Spring probes for electrical test fixtures also include such a separate plunger and spring contained in an outer barrel for use in testing electrical continuity between test points of circuits on a printed circuit board, for example. U.S. Pat. No. 4,773,877 to Kruger et al. discloses a contactor for an electronic tester in which the contactor includes a one-piece resilient contact pin having a guided plunger at one end and a spring section at the other end. The plunger section and spring section are integrally joined and formed from a common sheet metal piece. The particular form of the contactor shown in the Kruger '877 patent would not be useful as an electrical connector for carrying high current loads subjected to constant cycling. The Kruger '877 contactor also would not be useful for high-density spring contacts in a miniaturized connector adapted for mounting to a printed circuit board and also subjected to constant cycling.
The present invention overcomes the drawbacks of the Kruger '877 contactor by providing a solid metal compliant high current carrying electrical connector, and in another form of the invention, by providing solid metal compliant contacts for several forms of miniaturized connectors adapted for mounting to printed circuit boards.
One prior art high current electrical connector commonly used in subway cars, for example, includes a movable plunger biased by a compression spring contained in an outer barrel. The plunger has a drilled cross-hole that receives a copper braid extending along opposite sides of the plunger and through the cross hole. The ends of the braid are soldered to the barrel. The braid is used to carry the high current independently of the spring. There are many disadvantages of this connector including its high cost of parts and assembly. In addition, the spring can take a set from cycling during use, and the braid is subject to fatiguing wear during use.